1. Field of the Invention
The present invention relates to the field of telecommunications. More particularly, the present invention relates to implementing presence in a telecommunications network.
2. Background Information
Internet based instant messaging services have recently gained popularity. Popular commercial instant messaging services contain a presence component, meaning that they maintain an active and dynamic record of the availability and status of their subscribers. The presence of a subscriber typically indicates whether this subscriber is online and available to participate in communications sessions with other subscribers. When compared to traditional telephony, instant messaging with presence provides several advantages. First, the session initiating party knows the status of the session terminating party or parties in advance. Second, the recipient may affect the presence status by indicating to the system an unwillingness to communicate with certain or all parties.
Presence information has been expanded beyond the limited ‘login status’ to include other types of information, such as geographical location, device identity and capabilities, network address at which the subscriber is available, preferred mode of communication, etc. Industry forums (such as the Open Mobile Alliance (OMA), Internet Engineering Taskforce (IETF), and Presence and Availability Management (PAM) forum) have provided specifications on the inter-working, functionality, and interfaces of presence systems.
It would be desirable to extend the application of presence beyond instant messaging to telephony.